Vacuum piston mechanism for locomotive drifting-valves.



J. BILLINGHAM & G. F. KAHLER.

V'AGUUM PISTON MECHANISM FOR LOCOMOTIVE DRIPPING VALVES.

APPLICATION FILED JULY 17,1914.

11 1 1 ,374, Patented Nov. 10, 1914.

WITNESSES lNvE NToFks l a/n u. Ff/WW W C mu%' PATENT OFFICE.

V UNITED STATES JOSEPH BILLING-HAM AND CHARLES F. KAHLER, OF SGHENECTADY, NEW YORK.

VACUUM.PISTON MECHANISIG FOR LCOIVJIO'JEI'VTEI DRIFTING-VALVES.

1,116,374. Original application filed ,April 24. 1914, Serial No.

Specification of Letters Patent.-

Ifatented Nov. 10. 1914-.

834,054. Divided and this application filed July 17.

1914. Serial No. 851,442.

Toall whom it may concern.-

Be 1t known that we. Josnrn BILLINGI-IAM "and/Cinemas F. KAHLER, both of Schenecthe casing,

tady, inthe county of Schenectady and State of New York, have invented a certain new and useful Improvement in Vacuum Piston Mechanism for Locomotive Drifting- Valves, of which improvement the following is a specification.

In an application for Letters Patent for drifting valves for locomotives. filed by us pril 24. 1914. b'er. X0. 834,054, of which this application is a division. we have set forth an admission valve mechanism which is controlled by a vacuum piston mechanism, which latter mechanism constitutes the sub ject matter of our pr sent application.

The improvement claimed is hereinafter fully set forth.

The accompanying drawing is a vertical central section through a vacuum piston mechanism illustrating an embodiment of our invention.

In the practice of our invention we provide a vacuum piston chest or casing, 3, which is most conveniently located on one of the valve chests of the locomotive, in the position ordinarily occupied by the relief valve, the casing communicating, at its bottom, with the space within the valve chest on he admission side of the distribution valve, and being connected to the valve chest by a screw shank, 3, or through the intermediation of a ball joint, if preferred. An open topped piston chamber, 3, is formed 1n 3, adjacent to a detachable cap, the top of the casing, and

3, which closes substantially smaller a central passage, 3 of diameter than the piston chamberx. extends downwardly therefrom in the casing, its lower end being closed by a screw plug, 3. An air port, 3, extends from the passage, 3, near its upper end, to the atmosphere; an exhaust port, 3 extends from the passage to the atmosphere, a short distance above-the lower end of the passage; and a drain port, 3*, leads out of the passage at or immediately adjoining its lower end. A pressure inlet port, 3, leads into the passage, 3 and a pressure outlet port, 3", leads out of said passage, below the pressure inlet port. 7

A fluid pressure supply pipe, any suitable source of fluid pressure l, leads from s pp y,

l brake apparatus of the locomotive. to a connection with the pressure inlet port: 3'. and a fluid pressure delivery pipe. 0. leads from a connection with. the pressure outlet port. 3", to an admission valve mechanism. which. as it does not form part of our precent invention. will not be herein described. A properly packed piston. T. is fitted in the piston chamber. 3", and is secured on a piston stem. T, which extends dowlm'ardlv in the central passage. 3 of the casineniand l carries three pistons, S, K), and 10. littin the passage. 3. and making tight joints herewith by suitable packing. in the normal or inactive position of the parts, the piston. 8, stands between the piston clui'mber and the fluid pressure supply pipe; the piston. 9. be tween the fluid pressure supply pipe and the fluid pressure delivery pipe; and the piston, 10, below, and clear of. the exhaust port. 3

The fluid pressure supply pipe. 4. may.instead of being connected to thcmain air reservoir. lead from any suitable location in the steam space of the boiler, and, in such case, is controlled by a suitable manually operable cock or alve. Either compressed an or steam may, without departure from the spirit and operative principle of our invention, be used for actuating the motor piston or the admission valve mechanism.

In the operation of the vacuum piston mechanism above described, the steam supply valve of the locomotive having been opened, and the locomotive running under steam, 2'. 6. with its throttle "alve open, the pistons, T, 8, 9, and 10, of the vacuum piston mechanism, being subject to valve chest pressure, acting on the upper side of the piston, 7, remain in the ordinary normally seated positions shown in Fig.3.

\l'hen the locomotive is drifting or running with its throttle closed, a partial vacuum will. by the reciprocation of the pistons in the cylinders, be formed therein, in the distribution valve chests on the admission side of the valves, and in the steam supply connections leading from the throttle valve to the distribution valve chests. The pressure previously acting on the upper side of the piston, 7, will be correspondingly reduced, and atmospheric pressure, acting on the lower side of said piston through the port, 3', will raise it, and the connected pistons, 8, 9, and 10, thereby bringing the fluid pressure supply pipe, 4, into communication with the fluid pressure delivery pipe, 6. The pressure delivered from said pipe to the admission valve mechanism, will actuate said mechanism to effect the admission of steam to the distribution valve chests and cylinders of the locomotive, which admission will con tinue during the drifting of the locomotive, as fully set forth in our application Ser. No. SSA-,OS L atoresaid.

soon as the cylinder pressure exceeds that of the atmosphere, the piston, 7, will be depressed, the air below it being exhausted through the port, 8 the piston, 9, will cut oil communication between the fluid pressure supply pipe, i, and the fluid pressure delivery pipe, 6; and the fluid pressure in the latter pipe will be exhausted therefrom through the port, 3*. The delivery or" pressure to the admission valve mechanism, through the pipe, 6, being thereby stopped, the supply of steam to the cylinders by the admission valve mechanism will be cut off.

We claim as our invention and desire to secure by Letters Patent:

A vacuum. piston mechanism for locomotive drifting valves, comprising a casing or 21,1 teem chest having an open topped piston chamher, a removable cap closing the casing above in the central passage, air passages leading into the plston chamber and 1nto the central passage, respectively, and pistons fixed on the piston stem and fitting the central passage, said pistons controlling communication between the fluid pressure supply and delivery ports, between the piston chamber and the fluid pressure supply port, and between the fluid pressure delivery port and the atmosphere, respectively.

JOSEPH BILLINGHAM. CHARLES F. KAHLER. Witnesses W; S. FRAME, J. H. WRIGHT. 

